Dominic Grieve, the Attorney General, has faced calls to stop Scotland Yard
using the Official Secrets Act to make journalists reveal their sources.

The Metropolitan Police is seeking a court order under the act — intended to protect national security — that would compel a newspaper to hand over documents relating to the News International phone-hacking scandal.

The police force’s move prompted a growing political backlash, and was widely criticised at the Liberal Democrat conference in Birmingham yesterday.

Don Foster, the party’s spokesman on media issues, told a fringe meeting that Mr Grieve should use his “discretion” as the Government’s chief law officer to stop the Met using the Act against The Guardian.

“The Attorney General has the opportunity to use this power,” Mr Foster said.

Met investigators want the newspaper to hand over material relating to its reporting of phone-hacking at the News of the World, particularly the revelation that the voicemail of Milly Dowler, the murdered 11-year-old schoolgirl, was illegally accessed.

That story led to the closure of the News of the World and prompted fresh police inquiries into allegations of illegal newsgathering activities at News International. Sir Harold Evans, a former editor of The Times and The Sunday Times, also suggested Mr Grieve should step in.

“I cannot believe that the Attorney General will let this case of uniformed bullying go forward,” he said, suggesting that the action would breach the Human Rights Act.

Hugh Grant, the actor, also criticised the police force’s legal move.

Mr Grant, who is thought to have been a victim of phone hacking, is campaigning for stronger regulation of the press.

He told a meeting at the Lib Dem conference that the police action was “worrying and deeply mysterious” and suggested that Scotland Yard was not truly interested in uncovering the truth about hacking and other wrongdoing.